Research on Establishment and Solution of the Model of Drill String Vertical Vibration

Aiming at the problem of the drill string vertical vibration on rotary drilling, the dynamic model of the drill string vertical vibration which caused by the interaction of drill bit and rock and elastic deformation of drill string is established by the theory of flexibility pole and cell method. The finite difference method is used to solve the drill string vertical vibration model under the given initial conditions and boundary conditions. In this study, MATLAB is employed to calculate results of displacement, velocity and acceleration of drill string vertical vibration in order to lay theoretical basis for further studying actual law of movement and dynamics performance of the drill string vibration.